1. Field of the Invention
The present invention relates to a television program recording and reproducing system for recording a television program on a magnetic tape based on television program data form a text broadcast signal, and more particularly, to such a system which is arranged to make the contents of recorded programs readily available by displaying a list thereof, and to reproduce a desired program from its beginning by selecting the desired program from the list of recorded programs.
2. Description of the Related Art
Text broadcasts which use conventional television frequencies to provide static image data including text and graphics have become commercially available in recent years, and television receivers having a built-in text broadcast reception function have been developed and marketed.
A conventional text broadcast receiver is described hereinbelow with reference to the accompanying figures. FIGS. 2a and 2b illustrate the text broadcast data transmission procedure and describe the data transmission sequence in text broadcasting.
Text broadcast data is transmitted in four vertical blanking periods, 14H (277H) through 16H (279H) and 21H (284H), of the conventional television signal. In each 1H of the four blanking periods, the following text broadcast data are multiplexed: synchronization data; prefix (PFX); data block; and check code. The check code is used for error correction and data block extraction, and the data block which carries the informative data is combined with the data block obtained from another 1H line to form a data group. Each data group comprises the data group header, data header, and data unit. The data group header includes a data group identification code which indicates whether the data following the header is program management data, page data, or program index data. The data header shows the program number of the following data unit, and contains a data header parameter which indicates whether the data unit is program management data, page data, continued data, or program index data. The data unit is the collection of data which is actually processed, and is classified by the data unit parameter indicating the data type (e.g., text, melody, photographic).
The construction of a conventional text broadcast receiver is described below.
FIG. 4 is a block diagram of a conventional text broadcast receiver including: a data extraction section 20 for extracting the text broadcast signal multiplexed with vertical blanking periods of the video signal, applying error correction, and extracting the data block; a data group construction section 21 for constructing the data groups from the data blocks extracted by the data extraction section 20; a data identifier section 22 for identifying whether a data group constructed by the data group construction section 21 is program index data or page data, in accordance with the information obtained from a data group identification code, data header parameter, data unit parameter, and program number data; a program index processing section 23 for processing program index data so as to manage the program numbers of the text broadcast programs transmitted on that channel; a decoding section 24 which processes the page header and interprets the text, melody, and photographic data according to the type thereof as identified by the data unit parameter; and a display controller 25 which converts the data interpreted by the decoding section 24 to display data (RGB data) for viewing on the display device.
The operation of the conventional text broadcast receiver described above will now be explained. The first operation step is extraction of the text broadcast signal multiplexed with the vertical blanking period of the input video signal by the data extraction section 20, followed by error correction and data block extraction. Data groups are then constructed from the extracted data blocks by the data group construction section 21. The data identifier section 22 then determines, using the data group identification code in the data group header and the data header parameter and program number information in the data header, whether the data group is program index data or page data. If the data group is program index data, program number data management processing is applied for the text broadcasts on that channel by the program index processing section 23; if the data group is page data, the decoding section 24 applies interpretative processing to the encoded text, graphic, sound, and other data according to the data type (including text, melody, photographic) identified by the data unit parameter. The interpreted page data is then converted by the display controller 25 to data (RGB data) for display on the display device.
Text broadcasts offering a variety of information services, including news and weather reports, are thus provided by transmitting data according to the transmission procedure thus described for interpretation of the encoded text and graphic information according to the transmission procedure by the text broadcast receiver for display of static image data on the television screen.
More recently, however, there have been proposals to further expand text broadcasting services while maintaining compatibility with existing text broadcast standards by expanding the transmission protocol (defining new transmission parameters); one such service makes it easier to set VCR recording reservations by encoding television program table information (including program titles and the date and time of the broadcast) and transmitting this data as the data unit data. Unfortunately, however, conventional text broadcast receivers are not compatible with such expanded transmission standards, and these users are therefore unable to utilize such new services.
At the same time, however, the typical procedure followed to set a VCR recording reservation is complicated and hard to understand, making it difficult for novices and people unaccustomed to video and audio equipment to use the VCR timer recording functions. There is therefore a strong consumer desire for a simplified recording reservation operation.
There is also a consumer demand for a television program recording and reproducing system which is capable of easily displaying the contents of recorded programs and easily reproducing a desired recorded program from its beginning. That is, television programs are often recorded in a recording medium, such as a magnetic video tape. However, when a plurality of programs are recorded on a plurality of tapes, it is difficult to know on which tape and where on the tape any particular program is recorded unless the tapes are well organized.
Hereinbelow, an example of the conventional television program recording and reproducing system will be described with reference to FIG. 5.
FIG. 5 is a block diagram showing the construction of a conventional television program recording and reproducing system, which includes: a recording time information input means, or a timer, 201 for inputting recording information such as channel, date, recording start time, recording end time, program title to be recorded, etc., for recording television signals; a recording operation control means 202 for starting or ending the recording operation based on the recording time information inputted by the recording time information input means 201; an index write-in means 228 for writing a search index information indicating the recording start position into a recording medium at the start of recording; an index read-out means 205 for reading out, at the start of reproducing, the index information written in by the index information write-in means 228; an index input means 29 for inputting the index number of the recorded program that is desired to be reproduced; an index search means 211 for searching the index number inputted by the index input means 229 from the recording medium; a stop/reproduce means 212 for stopping the search and reproducing the program which is found by the index search means 211; and a recording/reproducing section 213 for recording a television signal on a recording medium and for reproducing the recorded television signal.
The operation of such a television program recording and reproducing system will now be described.
In FIG. 5, when a television program is recorded using the timer 201, the recording program information such as channel, date, recording start time, recording end time, etc., are first inputted by the timer 201. The recording operation control means 202 reads the program as stored in the timer 201 and operates the recording/reproducing section 213 to record the program when the time comes. The index input means 229 operates at the recording time and reproducing time such that, during the recording, the index number as specified by the index input means 229 is recorded by the index write-in means 228, and during the reproducing, the index number having been written in by the index write-in means 228 is read out by the index read-out means 205 and the index number specified by the index input means 229 is search by the index search means 211.
When the index number specified by the index input means 229 and the index number detected by the index search means 211 match with each other, the searching stops and the reproducing starts by the stop/reproducing means 212.
However, the prior art system as described above has the following problems. By the above arrangement, it is not possible to record index numbers at the time of setting the timer. Furthermore, since the contents of recorded programs are not readily displayable, it is necessary to reproduce the recorded medium each time to know the contents thereof, or it is necessary to apply a label indicating the recorded contents on the tape (recording medium).
Furthermore, in the case where a plurality of programs are recorded on a single tape, a problem arises in that the searching for the beginning of the desired program takes time and labor.